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Featured researches published by Bertrand Piguet.


Archives of Ophthalmology | 1999

Photodynamic Therapy With Verteporfin for Choroidal Neovascularization Caused by Age-related Macular Degeneration: Results of a Single Treatment in a Phase 1 and 2 Study

Ursula Schmidt-Erfurth; Joan W. Miller; M. Sickenberg; Horst Laqua; Irene Barbazetto; Evangelos S. Gragoudas; Leonidas Zografos; Bertrand Piguet; Constantin J. Pournaras; Guy Donati; Anne Marie Lane; Reginald Birngruber; Hubert van den Berg; H. Andrew Strong; Ulrike Manjuris; Todd Gray; Mario Fsadni; Neil M. Bressler

OBJECTIVE To evaluate the safety and short-term visual and fluorescein angiographic effects of a single photodynamic therapy treatment with verteporfin with the use of different dosage regimens in patients with choroidal neovascularization (CNV) from age-related macular degeneration. DESIGN Nonrandomized, multicenter, open-label, clinical trial using 5 dosage regimens. SETTING Four ophthalmic centers in North America and Europe providing retinal care. PARTICIPANTS Patients with subfoveal CNV caused by age-related macular degeneration. METHODS Standardized protocol refraction, visual acuity testing, ophthalmic examination, color photographs, and fluorescein angiograms were used to evaluate the effects of a single treatment of photodynamic therapy with verteporfin. Follow-up was planned through 3 months in 97 patients and for less than 3 months in 31 other patients. RESULTS The mean visual acuity change (and range of change) from baseline at the follow-up examination at week 12 after a single treatment with regimens 1 through 5 was -0.2 (-3 to +2), -0.9 (-9 to +5), -1.6 (-9 to +2), +0.4 (-8 to +7), and +0.1 (-8 to +9) lines, respectively. Only the highest light dose (150 J/cm2) in regimens 2 and 3, which produced angiographic nonperfusion of neurosensory retinal vessels, caused marked vision loss. Some cessation of fluorescein leakage from CNV was achieved without loss of vision when the light dose used was less than 150 J/cm2. Systemic adverse events were rare. Cessation of fluorescein leakage from CNV was noted in all regimens by 1 week after photodynamic therapy. Fluorescein leakage from at least a portion of the CNV reappeared by 4 to 12 weeks after treatment in almost all cases. Progression of classic CNV beyond the area of CNV identified before treatment was noted in 42 (51%) of the 83 eyes with classic CNV followed up for 3 months after a single treatment. Eyes in which the area of any CNV leakage at 12 weeks was less than at baseline had a significantly better visual acuity outcome (+0.8 line) than eyes in which CNV leakage progressed (-0.8 line). CONCLUSIONS Photodynamic therapy with verteporfin achieved short-term cessation of fluorescein leakage from CNV without loss of vision or growth of classic CNV in some patients with age-related macular degeneration. Except for nonperfusion of neurosensory retinal vessels at a light dose of 150 J/cm2, no other adverse events were of concern. Randomized clinical trials to investigate whether this new modality can preserve vision in patients with CNV secondary to age-related macular degeneration are justified.


Nature Genetics | 1999

A single EFEMP1 mutation associated with both Malattia Leventinese and Doyne honeycomb retinal dystrophy

Edwin M. Stone; Andrew J. Lotery; Francis L. Munier; Elise Héon; Bertrand Piguet; Robyn H. Guymer; Kimberlie Vandenburgh; Pascal Cousin; Darryl Y. Nishimura; Ruth E. Swiderski; Giuliana Silvestri; David A. Mackey; Gregory S. Hageman; Alan C. Bird; Val C. Sheffield; Daniel F. Schorderet

Malattia Leventinese (ML) and Doyne honeycomb retinal dystrophy (DHRD) refer to two autosomal dominant diseases characterized by yellow-white deposits known as drusen that accumulate beneath the retinal pigment epithelium (RPE). Both loci were mapped to chromosome 2p16-21 (Refs 5,6) and this genetic interval has been subsequently narrowed. The importance of these diseases is due in large part to their close phenotypic similarity to age-related macular degeneration (AMD), a disorder with a strong genetic component that accounts for approximately 50% of registered blindness in the Western world. Just as in ML and DHRD, the early hallmark of AMD is the presence of drusen. Here we use a combination of positional and candidate gene methods to identify a single non-conservative mutation (Arg345Trp) in the gene EFEMP1 (for EGF-containing fibrillin-like extracellular matrix protein 1) in all families studied. This change was not present in 477 control individuals or in 494 patients with age-related macular degeneration. Identification of this mutation may aid in the development of an animal model for drusen, as well as in the identification of other genes involved in human macular degeneration.


Graefes Archive for Clinical and Experimental Ophthalmology | 1998

Photodynamic therapy of subfoveal choroidal neovascularization: clinical and angiographic examples

U. Schmidt-Erfurth; Joan W. Miller; M. Sickenberg; A. Bunse; Horst Laqua; Evangelos S. Gragoudas; Leonidas Zografos; Reginald Birngruber; H. van den Bergh; Strong A; Ulrike Manjuris; Mario Fsadni; Anne Marie Lane; Bertrand Piguet; Neil M. Bressler

Abstract · Background: Conventional photocoagulation of subfoveal choroidal neovascularization (CNV) is often accompanied by visual loss due to thermal damage to adjacent retinal structures. Photodynamic therapy (PDT) allows vascular occlusion by selective photochemical destruction of vascular endothelial cells only. In a pilot study we evaluated the use of PDT in CNV. · Methods: In a clinical phase I/II trial, patients with subfoveal CNV were treated with PDT. Benzoporphyrin derivative monoacid ring A (BPD) was used as sensitizer at a drug dose of 6 mg/m2 or 12 mg/m2. Irradiation was performed via a diode laser emitting at 690 nm coupled into a slit lamp. Safe and maximum tolerated light doses were defined by dose escalation from 25 to 150 J/cm2. Photodynamic effects were documented ophthalmoscopically and angiographically. · Results: Sixty-one patients received a single course of BPD-PDT. Preliminary results suggest no damage to retinal structures within the treated area clinically. Retinal perfusion was not altered, while CNV demonstrated immediate absence of fluorescein leakage in the majority of lesions subsequent to PDT. At optimized parameters (6 mg/m2 and 50 J/cm2) complete cessation of leakage from classic CNV occurred in 100% of cases at 1 week and in 50% at week 4. In 70–80% of classic CNV, leakage reappeared at week 12, but markedly less than before treatment. · Conclusion: PDT allows temporary absence of leakage from CNV with preservation of visual acuity. The long-term prognosis of CNV secondary to age-related macular degeneration treated with repeated courses of PDT is being evaluated in a phase III trial.


Evidence-based Eye Care | 2000

Photodynamic Therapy With Verteporfin for Choroidal Neovascularization Caused by Age-related Macular Degeneration

Joan W. Miller; Ursula Schmidt-Erfurth; M. Sickenberg; Constantin J. Pournaras; Horst Laqua; Irene Barbazetto; Leonidas Zografos; Bertrand Piguet; Guy Donati; Anne Marie Lane; Reginald Birngruber; Hubert van den Berg; H. Andrew Strong; Ulrike Manjuris; Todd Gray; Mario Fsadni; Neil M. Bressler; Evangelos S. Gragoudas

OBJECTIVES To evaluate safety and short-term visual acuity and fluorescein angiographic effects of photodynamic therapy (PDT) after retreatments with verteporfin for choroidal neovascularization (CNV) in age-related macular degeneration (AMD) that demonstrated fluorescein leakage after at least 1 course of PDT. DESIGN Nonrandomized, multicenter, open-label phase 1 and 2 clinical trial using 2 different retreatment dosage regimens. SETTING Four ophthalmic centers in Europe and North America providing retinal care. METHODS Standardized protocol refraction, visual acuity testing, ophthalmic examinations, color photographs, and fluorescein angiograms were used to evaluate the results of multiple PDT treatments. Two regimens (regimens 2 and 4) for treatment and retreatment were chosen from 5 used in a single-treatment study. Both regimens used a verteporfin dose of 6 mg/m2 infused for 10 minutes. However, regimen 2 used a light dose of 100 J/cm2 applied 20 minutes after the start of the verteporfin infusion, whereas regimen 4 used a light dose of 50, 75, or 100 J/cm2 applied 15 minutes after infusion commenced. Posttreatment evaluations were planned in 31 participants up to 3 months after up to 2 retreatments given at 2- or 4-week intervals after initial PDT treatment. Similar posttreatment evaluations were planned after retreatments in 5 additional participants who were reenrolled some time more than 12 weeks after an initial PDT treatment. RESULTS The average visual acuity change for the 31 participants who had retreatment within 2 to 4 weeks after the initial treatment and a follow-up examination 16 to 20 weeks after the initial treatment was 0.2 lines (range, -4 to 4 lines) in regimen 2 and -1.0 line (range, -5 to 3 lines) in regimen 4. Similar outcomes were noted in the 5 reenrolled participants. Cessation of fluorescein leakage from classic CNV for at least 1 to 4 weeks could be achieved without loss of visual acuity after at least 2 treatments in 2 (6.5%) of 31 patients. Similar to single-treatment effects, the disappearance of leakage was documented regularly at 1 week after each retreatment. Fluorescein leakage reappeared by 4 to 12 weeks after a retreatment in almost all cases. However, compared with baseline, leakage activity appeared to be reduced after multiple PDT courses. For the 31 patients who had follow-up for 3 months after the last retreatment and had received retreatment 2 to 4 weeks after the initial treatment, progression of CNV beyond the area identified before the retreatment was noted in 10 (48%) of the 21 eyes with classic CNV in regimen 2 and 9 (90%) of 10 eyes in regimen 4. The rate and severity of ocular or systemic adverse events were not increased by multiple applications. CONCLUSIONS Multiple applications of PDT with verteporfin achieve repetitive, short-term cessation of fluorescein leakage from CNV secondary to AMD, without loss of visual acuity. This strategy can be used in randomized clinical trials investigating the efficacy of verteporfin in PDT for recurrent fluorescein dye leakage from persistent or recurrent CNV, following an initial or subsequent PDT treatment, with maintenance of visual acuity. Retreatments may achieve progressive cessation of leakage and prevent further growth of CNV and subsequent visual loss.


American Journal of Ophthalmology | 1992

Evolution of Age-related Macular Degeneration with Choroidal Perfusion Abnormality

Bertrand Piguet; Inge B. Palmvang; Ian H. Chisholm; Darwin Minassian; Alan C. Bird

Prolonged choroidal filling on fluorescein angiography in age-related macular degeneration is thought to indicate diffuse thickening of Bruchs membrane. To test the importance of this clinical sign, we reviewed the evolution of disease in eyes of patients with good visual acuity and a readable transit phase of fluorescein angiography at the time of recruitment into a longitudinal study of age-related macular degeneration. Ninety-six eyes satisfied these criteria. Of the 32 eyes with prolonged choroidal filling, 12 (38%) lost two or more lines, of visual acuity by two years, whereas only nine of 64 (14%) eyes with normal choroidal filling did so. The difference was caused by the higher incidence of geographic atrophy in the first group. The proportion of eyes that developed subretinal neovascularization was the same in the two groups, and no pigment epithelial detachments occurred. These findings indicate that this clinical sign has implications concerning visual prognosis in age-related macular degeneration.


Retina-the Journal of Retinal and Vitreous Diseases | 1998

MORPHOMETRIC CHARACTERISTICS OF TRAUMATIC CHOROIDAL RUPTURES ASSOCIATED WITH NEOVASCULARIZATION

Michel Secrétan; M. Sickenberg; Leonidas Zografos; Bertrand Piguet

Purpose: To define the morphometric characteristics of indirect choroidal ruptures associated with choroidal neovascularization (CNV). Methods: A total of 79 eyes that had sustained traumatic indirect choroidal ruptures was studied retrospectively. Color pictures of the fundus and fluorescein angiograms were available in all cases, and patients were followed for at least 1 year. Eyes that were free of CNV constituted Group I; eyes that developed CNV constituted Group II. Baseline characteristics of both groups, including age, sex, and visual acuity, were recorded. Distance of indirect choroidal ruptures from the center of the fovea and morphometric characteristics of the ruptures were calculated using image analysis software (Image 1.60; National Institutes of Health, Bethesda, MD). Results: A total of 63 eyes (79.7%) free of CNV was included in Group I and 16 eyes (20.3%) that developed CNV were included in Group II. Morphometric analysis showed a greater distance between the indirect choroidal rupture and the center of the fovea in Group I than in Group II (median, 1480 μm versus 612 μm; P = 0.009). In addition, the length of the rupture was shorter in Group I than in Group II (median, 3054 μm versus 4504 (μm; P = 0.03). Conclusions: Two significant factors associated with the presence of CNV in case of traumatic choroidal rupture were identified and quantified: the proximity of the rupture to the center of the fovea and the length of the rupture. Both should be considered as risk factors for the development of CNV and monitoring should take them into account.


Ophthalmologica | 2000

Indocyanine Green Angiographic Findings in Choroidal Hemangiomas: A Study of 75 Cases

Ann Schalenbourg; Bertrand Piguet; Leonidas Zografos

Indocyanine green (ICG) angiography is a new diagnostic modality that was suggested, in small series, to provide a typical angiographic pattern in cases of choroidal hemangioma. Our study, through an exceptionally large series of 75 patients, assessed in a prospective way whether a typical ICG pattern of choroidal hemangioma exists and what would be its possible variations. The most constant feature is the sequence of the different ICG angiographic phases. The arterial phase demonstrates the filling of intratumoral vessels on a hypofluorescent tumoral background. During the venous phase, the hemangioma reaches a stage of maximal ICG-A fluorescence, with superimposed hyper- and hypofluorescent spots. Sturge-Weber cases have also extratumoral hyperfluorescent spots. The late phase shows a hypofluorescent lesion with residual hyperfluorescent caverns and a well-delineated, but complex border structure.


Ophthalmologica | 1998

Bilateral Optic Papillitis Following Mycoplasma pneumoniae Pneumonia

Elena Millá; Leonidas Zografos; Bertrand Piguet

Mycoplasma pneumoniae is an atypical bacterium that can cause a great variety of respiratory infections and be responsible for ocular involvement such as conjunctivitis, anterior uveitis and very rarely optic neuropathy. We report herein an additional case of bilateral optic disc swelling with profound visual loss following Mycoplasma pneumoniae pneumonia and review the world literature on the ocular manifestations associated with this pathogen.


Ophthalmologica | 2000

Indocyanine Green Angiography in Fundus flavimaculatus

Joan Schwoerer; Michel Secrétan; Leonidas Zografos; Bertrand Piguet

Purpose: To describe the characteristic findings of fundus flavimaculatus (Stargardt disease) as seen on indocyanine green angiography. Methods: Twelve eyes of 6 consecutive patients with fundus flavimaculatus were studied by fundus color photographs, fluorescein angiography and indocyanine green angiography. Results: Indocyanine green angiography allowed visualization of small, clearly demarcated areas in which hypofluorescence increased over time, leading eventually to a large reticular pattern with small areas of normal-appearing choroid encircled by a well-defined network of hypofluorescent curvilinear lesions. These hypofluorescent flecks were present in all 12 eyes but corresponded only partially to the yellow flecks visible on biomicroscopy of the fundus. The peripapillary area was well preserved on indocyanine green angiography and the periphery did not show any visible abnormalities. Conclusions: The hypofluorescent curvilinear areas visualized on indocyanine green angiography form a reticular pattern that is similar to the polygonal shape of the watershed zones between terminal choroidal arterioles, which supply the choriocapillaris. These dark areas may reflect choriocapillaris defects secondary to lysis of lipofuscin-engorged retinal pigment epithelial cells. The typical lesions of fundus flavimaculatus thus seem to be situated in areas of least vascular supply. Their absence in the peripapillary area, which benefits from anastomotic vascular connections, would support this hypothesis.


Retina-the Journal of Retinal and Vitreous Diseases | 1998

Linkage of Autosomal Dominant Radial Drusen (Malattia Leventinese) to Chromosome p 16???21

Elise Héon; Bertrand Piguet; Francis L. Munier; S. R. Sneed; Craig M. Morgan; S. Forni; G. Pescia; Daniel F. Schorderet; C. M. Taylor; Luan M. Streb; C. D. Wiles; D. Y. Nishimura; Val C. Sheffield; Edwin M. Stone

OBJECTIVE To identify the chromosomal location of the gene involved in the pathogenesis of autosomal dominant radial drusen (malattia leventinese). PATIENTS Eighty-six members of four families affected with radial drusen; one family of American origin and three families of Swiss origin. METHODS Family members were clinically examined for the presence of radial drusen. Affected patients and potentially informative spouses were genotyped with short tandem repeat polymorphisms distributed across the autosomal genome. The clinical and genotypic data were subjected to linkage analysis. RESULTS Fifty-six patients were found to be clinically affected. Significant linkage was observed between the disease phenotype and markers known to lie on the short arm of chromosome 2. The maximum two-point lod score (Zmax) observed for all four families combined was 10.5 and was obtained with marker D2S378. Multipoint analysis yielded a Zmax of 12, centered on marker D2S378. The lod-1 confidence interval was 8 cM, while the disease interval defined by observed recombinants was 14 cM. CONCLUSIONS The gene responsible for autosomal dominant radial drusen has been mapped to the short arm of chromosome 2. This is an important step toward actually isolating the disease-causing gene. In addition, this information can be used to evaluate other familial drusen phenotypes such as Doynes macular dystrophy for a possible allelic relationship.

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Evangelos S. Gragoudas

Massachusetts Eye and Ear Infirmary

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Neil M. Bressler

Johns Hopkins University School of Medicine

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Anne Marie Lane

Massachusetts Eye and Ear Infirmary

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Joan W. Miller

Massachusetts Eye and Ear Infirmary

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Mario Fsadni

Ciba Specialty Chemicals

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